Yartiques ... to kinda answer your question about your 2 1859's that look different. The 1859's are all bronze (or were supposed to be). We did a study in 2012 and published it in the Canadian Numismatic Journal (March issue) on the "brass" 1859's to see if we could nail down what ensued to have brass cents. There are less than about 10 known and we found that they most probably were the result of improper mixing of the alloy in the pot when making the ingots. The ingots were then rolled into sheets and planchets cut from them.

The bronze for the 59's, that came from Heaton but were minted by the RCM, was supposed to be 95 CU, 4 SN and 1 ZN. To really be called "brass" it should be 67-85 CU with a much higher Zinc than tin in the remainder to make 100. So we wanted to take a large, random, sample of coins to see what we found.

I had a hoarde of nearly 1000 1859's, so we XRF'd about 500 or so for the study to see what we got for what the range of alloy %'s. We tried to throw more coins into the mix that looked "yellowish", one of the visual clues as to brass vs bronze. We found aloys from 90.96 Cu, .32 Zn, 2.87 Sn and no lead(Pb).... to 95.98 Cu, 1.85 Zn, 6.29 Sn & .76 Pb. Those %'s marked the highest concentrations of each alloy element and, similarly, the lowest. We had some that were vaguely close to brass, but none that could be considered so. For you mathematics fans out there, you can see that no single coin had either of the above percentages .. they were just the high and low % of each metal that we found.

It was our unanimous conclusion that the brass cents out there (or claim to be) were the result of improper mixing of the alloy metals in the crucible/vat that was then poured into the small brick molds. Just like pouring water out of a glass, either the top water in the glass actually comes out last (surface tension) or the heaviest stuff comes out last. Only a portion of the metal alloy in the brick would need to be lower in Cu and higher in Zn ... to have it come out in specific areas on the rolled sheet from which the planchets were cut.

Very few of the known "brass" cents have been XRF'd or lab-tested to see what the actual alloys were. Those that have tend to support our hypothesis. For years, "brass" cents were determined by the Grading Companies by scratching the edge of the coin with a diamond or glass and then looked at the scratch in the sunlight (Not under incandescent light) to see if it looked "yellow"... a far from scientific test. There are any number of household cleaning agents found under your sink that can turn a bronze 1859 into a yellow-looking coin. That is just caused by the chemical reaction with the highly-reactive copper in the coin. If you, Yartiques, have 2 1859's that look different, I can most heartedly suggest that they are bronze, not brass, and that one of them got too close to a cleaning agent.

Yartiques ... to kinda answer your question about your 2 1859's that look different. The 1859's are all bronze (or were supposed to be). We did a study in 2012 and published it in the Canadian Numismatic Journal (March issue) on the "brass" 1859's to see if we could nail down what ensued to have brass cents. There are less than about 10 known and we found that they most probably were the result of improper mixing of the alloy in the pot when making the ingots. The ingots were then rolled into sheets and planchets cut from them.
Thank you so much for such thorough information.

The bronze for the 59's, that came from Heaton but were minted by the RCM, was supposed to be 95 CU, 4 SN and 1 ZN. To really be called "brass" it should be 67-85 CU with a much higher Zinc than tin in the remainder to make 100. So we wanted to take a large, random, sample of coins to see what we found.

I had a hoarde of nearly 1000 1859's, so we XRF'd about 500 or so for the study to see what we got for what the range of alloy %'s. We tried to throw more coins into the mix that looked "yellowish", one of the visual clues as to brass vs bronze. We found aloys from 90.96 Cu, .32 Zn, 2.87 Sn and no lead(Pb).... to 95.98 Cu, 1.85 Zn, 6.29 Sn & .76 Pb. Those %'s marked the highest concentrations of each alloy element and, similarly, the lowest. We had some that were vaguely close to brass, but none that could be considered so. For you mathematics fans out there, you can see that no single coin had either of the above percentages .. they were just the high and low % of each metal that we found.

It was our unanimous conclusion that the brass cents out there (or claim to be) were the result of improper mixing of the alloy metals in the crucible/vat that was then poured into the small brick molds. Just like pouring water out of a glass, either the top water in the glass actually comes out last (surface tension) or the heaviest stuff comes out last. Only a portion of the metal alloy in the brick would need to be lower in Cu and higher in Zn ... to have it come out in specific areas on the rolled sheet from which the planchets were cut.

Very few of the known "brass" cents have been XRF'd or lab-tested to see what the actual alloys were. Those that have tend to support our hypothesis. For years, "brass" cents were determined by the Grading Companies by scratching the edge of the coin with a diamond or glass and then looked at the scratch in the sunlight (Not under incandescent light) to see if it looked "yellow"... a far from scientific test. There are any number of household cleaning agents found under your sink that can turn a bronze 1859 into a yellow-looking coin. That is just caused by the chemical reaction with the highly-reactive copper in the coin. If you, Yartiques, have 2 1859's that look different, I can most heartedly suggest that they are bronze, not brass, and that one of them got too close to a cleaning agent.

Yartiques: I think that you should start a new thread, specifically on the Canada 159 large cents so that it doesn't appear that we have hijacked this excellent thread on the different Canadian denominations/mintage years. I'll then ask the moderator to move my "brass" post to your new thread and it will be available for use by others with the same "brass" question.... and we won't be horning in on this thread.